When an ionizing radiation beam is applied to a radiation target (e.g. a patient or other object) it is often important to know precisely the radiation dose pattern imparted to the radiation target. Specifically it can be important to know the quantity of radiation delivered at each point within the radiation target. Ionizing radiation is applied to objects in numerous settings including radiation sterilization, materials processing, radiological imaging and radiation therapy for treatment of disease. Ionizing radiation is also used in other ways.